Would you... AFR heads/cam/carb a 454, or save for a 540?

[zimm17]

Still floating out here on deployment with lots of time to dream about the Donzi.

My 454 magnum runs perfect and has about 25 hours on it. I'm thinking about putting on a set of AFR 315 CNC heads, Crane roller cam, roller rockers, and a Nickerson Carb on it. Maybe MSD ignition. Should get me max HP out of the engine and cost about $6,000 in parts.

The other option is not dump any money into the motor, and someday build up a 540. Great idea, but they cost $15,000-$20,000 depending on the builder. That's what the boat is worth!

The nice thing about the AFR heads is that they can be used on a 540 shortblock someday- so I consider it a good investment.

Or the forum can do me a favor and convince me that 400HP is good enough and to be happy with 71mph.

I was also thinking about a blower: cut a huge hole in the hatch, bolt on a 8-71 blower, go fast, look cool, but I'm sure it'll absolutely kill my gas milage. I really like going out for the day and only putting 10-20 gallons in it when I'm done.

[Ed Donnelly]

Zimm; Go big or go home. Easy for me to say as its not my money.
Procharge your 454 and the $10,000 you save will buy you a hell of a lot of gas.......Ed

[zimm17]

There is NO replacement for displacement...
Your talking to the wrong folks on the 540.... :) :)

'poodle,

Do tell. I've gotten quotes from Dyno-flo, Mesa, Roccard, JC performance, and few others over on the offshoreonly forums. All start at $15k and easily go to $20k for carb to oil pan 600HP 540's.

I'm going to research the Keith Eickert put-it-together-yourself but already machined engine kits. That might save me some bucks.

Nothing fancy, GM or Dart block, AFR heads and associated goodies.

[zimm17]

'Poodle, temping. What gen block? Let me think about that for awhile. dyno-flo sells assembled 540 shortblocks for $5k.

As for parts though- AFR heads loaded with inconel valves and hard anodize- $3000.

Flywheel? Balancer (Fluidamper or ATI- $300)

Crane roller cam, roller lifters, rods, roller rockers, roller timing chain= $1100

Oil pan, pump, timing cover, cool valve covers= 600+

Carb= $500 for BG marine, $1000 for nickerson

MSD ignition= $600

Bigger oil cooler, gasket set, bolt kit, misc stuff

Oh, don't know if the stock merc fuel pump/sea pump combo push enough fuel. I would have to research that.

I don't see how to do it for under $10k even doing the work myself.

[BigGrizzly]

Don't wast money on the 454, OSO 15000 for a good one is OK, Just last week we sold a 572 with 730Hp and almost the same torque for $15000.It only had dyno time on it. we sold it for bill due amount. there was over 33,000 in it. no blower normally asperated. Point is HP doesn't come cheap.

[Cuda]

540, or procharge the 454. Personally, I'd go 540.

[justleft]

Don't forget Exhaust !!!

Add another $3 to 4 thou

[justleft]

The Dana and Thunder style manifolds are great but at some point
the headers are needed. 600 HP ??

Inovation would only put CMI headers on the pair of de-tuned racing
468cid blower motors in my Scarab (670 hp).

But hey, I will bid on your Dana's when you put then on EBay !!!

[BigGrizzly]

Justleft, that is because you had a relativly small motor with high HP and most exhaust would choak it and cause engine harm with the restriction. They probably recomended elbow tops not sport tubes. Dave Spech use to work at CMI and built my Corsican Sport tubes.